Shock absorber



Feb. 16, 1954 J, E, GROSS 2,669,449

SHOCK ABSORBER Filed March 27, 1951 INVENTOR. ./ofo/ Q/oss. BY`

13M MM MITO/@Vn- Patented Feb. 16, 1954 UNITED STATES PATENT OFFICE SHOCK ABSORBER Joseph E. Gross, Swissvale, Pa.

Application March 27, 1951, Serial No. 217,860

5 Claims.

My invention relates to shock absorbers and, more particularly, to shock absorbers for use in conjunction with the operating power cables in power shovels and draglines.

One object of my invention is to provide for reducing the impact forces set up in the operation of power shovels and draglines.

Another object is to provide for greatly reducing, without much motion, the shocks and strains usually involved in the operation of the power cables in power shovels and other apparatus and machinery, and thereby increase the life and usefulness of such apparatus and machinery.

A further object is to provide a shock absorber for heavy operating cables which shall be simple to manufacture, install andrmaintain in operation.

A still further object is to provide a shock absorber for securing the dead ends of heavy power operating cables which will greatly reduce the wear and tear on such cables and greatly prolong their life and usefulness in operation.

For a better understanding of my invention, reference may be had to the accompanying drawing, in which:

Figure 1 is a view, in side elevation, of a power shovel embodying my improvement in shock absorbers;

Fig. 2 is an enlarged view of my improved shock absorber illustrated in Fig, 1;

Fig. 3 is a view in rear end elevation of the shock absorber illustrated in Fig. 2; and

Fig. 4 is a View in front elevation of the shock absorber illustrated in Fig. 2.

Referring more particularly to Fig. l, I have illustrated a power shovel comprising a base I mounted on the usual Caterpillar tracks II for rotatably supporting a shovel platform I2 upon which is disposed a cab I3. A boom I4 is mounted on the front end of the platform I2 to provide a movable support for a shovel stick I5. The boom I4 is attached to the platform I2 by a plurality of hinge bolts I6 so that its outer end may be raised or lowered by a pair of hoist cables I1 which connect the outer end of the boom to a suitable power means (not shown) in the cab I3.

The stick I is movably supported in the central portion of the boom by a stick saddle IB mounted on a shipper shaft I9, the outer ends of which are rotatably seated in suitable bearing brackets attached to the side members of the boom.

Fixed on the outer end of the stick I5 by means of a pair of brackets 2| and 22 is a shovel or bucket 23 having a plurality of teeth 24 and a lid 25. The lid is attached to the bucket bya hinged connection 25 so that it may be opened to discharge the loads picked up by the bucket. A bracket 2l is attached to the upper part of the bucket and provided with a pulley 28 for a flexible power device such as a bucket-hoisting cable 29. One end of the cable 29 is attached to the upper portion of the boom by my improved shock absorber 3l from which it passes over a sheave 32 on the outer end or the boom, thence through the pulley 28 on the bucket, thence over. another sheave (not shown) on the outer end of the boom, and from there to a power hoisting mechanism (not shown) in the cab I3.

Referring more particularly to Figs. 2, 3 and 4, the shock absorber 3l is illustrated as comprising a curved arm 33, a resilient compressible body such as a helical spring 34, and a supporting base member 35. The arm is disposed on the base with its convex side toward the base with its one end/petween a pair of projections 35 and 36a on the upper rear face of the base member and is hingedly secured in that position by a hinge bolt 31. A limiting lug 3B is cast or otherwise secured to the rear bottom portion of the arm to limit movement of the arm in an upward and back direction. The curved arm is Vprovided with a cable-receiving track or groove 39 in its outer curved face. The dead-end portion of the bucket-hoisting cable is seated in the groove and attached to the rear end of the arm by a fastening means such as a cable securing bracket 40.

In constructing the arm, it may be either cast or rolled and then machined to provide a smooth well-shaped groove or track for receiving the bucket-hoisting cable. Preferably, the curve of the curved portion of the arm 33 should be similar to that of the segment oi the sheave `32 over which the bucket-hoisting cable passes after it leaves the shock absorber and should have the same radius as that sheave so that the cable in its movement will be operating on curved surfaces of the same radius in both the shock absorber and the sheave. Also, the radius of the arm and the sheave should be in proper proportion to the size of the cable.

The spring element 34 of the shock absorber is mounted with its lower end disposed on a spring seat 4I xed on the base 35 and with its upper end engaged and maintained in position by a spring seat 42 which is hingedly attached to the movable end of the arm 33 by a pair of lugs 43 and 44 and a hinge bolt 45.

In operating the power shovel, any load on the bucket-hoisting cable will tend to pull the curved arm downwardly against the compression spring 34. Y Assuming that the load increases, as it increases it increases the downward movement of the free end of the curved arm thus permitting the cable to move more nearly toward a straight line position between the hinged end of the arm and the point at which the cable engages its sheave on; the endzoftheiboom.. Asfthe outer end of the curved arm moves downwardly and the cable moves more nearly to a straight line, the leverage point of contact of the cable with the curved portion of the arm shifts towar'd the:

hinged end of the arm. As the point of leverage shifts in accordance with any increase or der crease in the load on the cable; it permitsf. the spring to readily absorb any sudden increase in load Without much compressive movement andA thus easily prevents any.` sudden load from injunlously aiTecting. the: cable; or the apparatus on f Whicln itis used". Thus, it will. be seen` that my improved shock absorber will greatly reduce. the shockn and'v strains usually'involved' in the. operation'. ofiE power cables.; in; power shovels andy other apparatus. andk machinery.

Although. I- have illustrated. andv described only one specific; embodiment of my invention,

realize'. that.v it; is` susceptible o Wide application,

andz Ia do not'. desire'. toi belimited to the. precise construction, illustrated andY described.

I; claim as my.' invention:`

1:.v Inl a shock absorber for a power.V cable, a basenriember., aicurved-'arm having a cable track; on its convex surface, a hinge. means hngedly connecting one endiotbearm tothe base memberwith its concat/.e face. toward; the oase member; a; cable fastening.y device mount-edi on the arm'y at a-pointiadjacent tothezhingedend of the arm-, and" av coiledt spring disposed between the free end ofi the arm andi the base member for resiliently opposing movement of.' thei free end of the arnr towardlthebase member when: a load is appli'edi to4 the` cable.

2. In a shock absorber for a flexible power means, afbasemember, an arm having' aconvex surfacej with a track thereon for the exible -powerme'ans a hinge meansconnecting one end off the arm to: the-basel member with its convex surfaceAL away from the base member; a power means'fastening dev-iceVV mounted ony the arm at fa point adjacenttoits hingedv end, and a resilient means disposed between the free end of the arm and the base member for opposing movement of Vthe free end of the arm toward the base member when a load is applied to the iexible power means.

3.Y In a shock absorber for a cable, a base member, a resilient member disposed on one end portion of the base member, an arm having its one; end disposed; on the resilient member and its other end" hinge'diy connectedv toV the other end portion of the base member, said arm having a convex outer face provided with a track for the cable, and a fastening means for securing the dead-end of the cable to the track portion of the 'i armfata` point adjacent to its hinged end.

4..Asshock absorber comprising a base member, an arm having a curved surface provided wither-track, a hinge connecting one end of the arm to the base member, a cable fastening means mofuntedz'on the; track por-.tion ofv the: armv at a point near its hingediend,z and a-.resilient device disposed'.betweenl the. movable' end of the4 arm and the base member for resilientlyv opposing; move?- ment'; of the arm toward the basemembenW-hen aaload isf appliedto the cable.. Y

5i A shock .absorbercomprising. a basemember; ani armhaving a curved. track; portion; an. hinge connecting; one endv of` the'. track portion ofi the armto;` theV base` member,V a fastening means mounted, on the track.. portion of. the; arm; near its?l hinged end: for securing; af. flexible powerr de.- vice. thereto,A and a resilientJ device connected'. to

the arm and the base member for opposing movement. of.` the: track: portion. of. the. arm. toward; the base member; when. a.: load; isY applied to the` power device.

. JOSEPH E. GROSS;

References Cited; in the leof' this patent UNITED; STATES" PATENTS Number Name: Date.;

29.6.;965, Huberretral. Apr. 15, 1884 '108,653 Osgood: Sept.. 9, 1902 2,385,906V Zeilman Oct. 2,. 19.45 2,558,331; Rointer- June- 26, 17951 FOREIGN PATENTS Number Country Datekv 383,881 GreatY Britain Nov. 24, 1932 

